Friendly Industrial Ethernet Switch

Faster-than-PLC power cycling

Power cycling of switches and PLCs is generally required for plant-wide maintenance updates. Most managed switches can take approximately 3 minutes, if not more, to reboot because they have relatively low processing power. PLCs, on the other hand, operate by using simple ladder logic and power cycling normally takes less than one minute. Administrative-level nodes (such as SCADA and HMI) will have no access to control-level and device-level nodes until switches have completed POST (power-on self-test) diagnostics and the bootstrap loading process. The difference between the duration of power cycling times of PLCs and switches will not only delay maintenance efforts, it can even cause port lockouts in some older time-sensitive automation systems. Advanced managed switches are now capable of completing a power cycle in the 10-second range.